This disclosure relates generally to energy storage devices, and more particularly, to a modular assembly and cooling system for one or more energy storage devices, including capacitors, ultracapacitors, and batteries.
In conventional capacitor assemblies, a plurality of capacitor cells, ultracapacitor cells, batteries, or other energy storage devices are loosely held together, through securing components, within a housing that can subject the cells to a certain amount of external forces, including vibratory forces. In some cases, these forces can exceed the strength of the securing components. In such cases, vibratory action can dislodge, rotate, wear and/or destroy portions of the devices and connections within and/or between them. This situation can reduce the durability and lifespan of the energy storage devices.
Some energy storage devices, including those with capacitor assemblies, may use adhesive substances and thermal inserts between capacitor cells. These components can dissipate heat generated during operation and reduce rotation and dislodging of the capacitor cells within the assembly, but are typically placed between capacitors and may be located along or nearby the path of an electric current. To connect energy storage devices together, complex bonding mechanisms between numerous surfaces may be used. These design choices have proven to impair the performance of energy storage devices, and can limit the opportunity to make further modifications.
Some capacitor assemblies use bus bars with circular ends to connect capacitor cells to one another. These bus bars can be designed to fully surround each end of a capacitor cell or an electrode. These circular ends must be precisely machined as close as possible to the shape of the end of the capacitor cell for the bus bars to properly contact and connect with a device. This limitation can greatly increase manufacturing time and/or produce an imprecise fit, leading to faulty and/or inconsistent performance.
In previous energy storage devices, such as traditional capacitor cells, a terminal is attached to an end of the cell through a radial weld or radial interference fit at an interface between the cell and the terminal. These points of attachment used complex geometries, with weld bonds located at several points of contact. Attachment points according to previous designs could cause difficulty or added complexity in manufacturing processes. In addition, a radial weld or radial interference fit can also cause attachment points between the cell and terminal to perform inefficiently or include imprecise geometrical connections.
The passage of electrical currents through particular materials, including ultracapacitors, may cause certain materials in an assembly to experience temperature increases.